Problem: $\dfrac{4}{8} + \dfrac{8}{5} = {?}$
Explanation: $ = {\dfrac{4 \times 5}{8 \times 5}} + {\dfrac{8 \times 8}{5 \times 8}} $ $ = {\dfrac{20}{40}} + {\dfrac{64}{40}} $ $ = \dfrac{{20} + {64}}{40} $ $ = \dfrac{84}{40}$